Guidewires having a vapor deposited primer coat

Abstract

An intraluminal device having an adhesive primer coat formed of a carbonaceous material and a lubricious top coat of a hydrophilic polymeric material. The invention also comprises the methods of making such intraluminal devices. The primer coat of the invention may comprise pure carbon, or a carbon based material such as a polymer. Preferably, the primer coat has a thickness of about 0.1 to about 2 μm. In a presently preferred embodiment, the primer coat is applied using chemical vapor deposition (CVD), but in certain embodiments, physical vapor deposition (PVD) may be suitable. The deposited primer coat forms an effective substrate for adhesion of the hydrophilic polymer top coat.

What is claimed is:  
     
       1. A guidewire comprising an elongated core member and a flexible helical coil disposed about a distal end of the core member, the flexible helical coil having a primer coat formed of a carbonaceous material vapor deposited on at least a portion thereof, and a hydrophilic polymer top coat on at least a portion of the primer coat. 
     
     
       2. The guidewire of claim  1 , wherein the primer coat has a uniform thickness of not more than about 2 μm. 
     
     
       3. The guidewire of claim  1 , wherein the primer coat is selected from the group consisting of carbon, plasma polymerized nylon, plasma polymerized polyurethane, plasma polymerized polyethylene, and plasma polymerized hydrocarbons. 
     
     
       4. The guidewire of claim  1 , wherein the top coat is selected from the group consisting of poly(N-vinylpyrrolidone), and polyethylene oxide. 
     
     
       5. The guidewire of claim  1 , wherein the top coat has a thickness of about 0.0025 mm to about 0.015 mm. 
     
     
       6. The guidewire of claim  1 , wherein adjacent turns of the flexible helical coil are individually coated so that the primer coat and the top coat do not bridge the adjacent turns of the coil. 
     
     
       7. A method of making a guidewire having a lubricious surface, comprising applying a primer coat formed on a carbonaceous material on at least a portion of a flexible helical coil disposed about a distal end of an elongate core member of the guidewire by vapor deposition, and then applying a hydrophilic polymeric coat on at least a portion of the primer coat. 
     
     
       8. The method of claim  7 , wherein the primer coat is applied by chemical vapor deposition. 
     
     
       9. The method of claim  8 , wherein the primer coat is applied until the primer coat is about 0.1 μm to about 2 μm thick. 
     
     
       10. The method of claim  7 , wherein the primer coat is applied by physical vapor deposition.